Blood tracking system

ABSTRACT

A blood tracking system includes a light source having a first LED configured to emit light of a first color and a second LED configured to emit light of a second color. The light of the first color and the light of the second color are mixed to produce light of a third color when the first LED and the second LED are activated. The light of the third color highlights blood.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/195,371, filed Aug. 2, 2005, which claims the benefit of U.S.Provisional Application No. 60/598,289, filed Aug. 3, 2004, both ofwhich are incorporated herein by reference in their entirety.

BACKGROUND

The present invention relates generally to the field of blood tracking.In particular, the present invention relates to a portable lighting unitconfigured to track blood using a light emitting diode (LED)illumination system.

There are occasions in which it is useful to be able to easily identifysmall amounts of blood in a particular environment. For example, ahunter may wound an animal, such as a deer, that runs some distance awayfrom the hunter after being wounded. In such a case, the hunter wouldlike to follow the blood trail in order to find the animal. Small dropsof blood can be difficult to see on the ground and on foliage,especially in low light conditions. To aid the hunter, blood trackingsystems have been devised that help differentiate the red color of theblood from the rest of the environment. Such systems include theutilization of special filters placed on flashlights and/or specialgoggles or glasses that highlight the blood.

It would be advantageous to provide a portable lighting device thatgives the user true blood tracking capability in low-level lightingconditions by using the optical principle of color enhancement. Inparticular, it would be advantageous to provide a lighting device thatgives a distinct visual appearance to blood without requiring specialfilters on a light source or requiring the user to wear special glassesor goggles.

SUMMARY

One embodiment of the invention relates to a blood tracking system,comprising a light source comprising a first LED configured to emitlight of a first color and a second LED configured to emit light of asecond color. The light of the first color and the light of the secondcolor are mixed to appear as light of a third color when the first LEDand the second LED are activated; and wherein the light of a third coloris effective for highlighting blood.

Another embodiment of the invention relates to a flashlight fordetecting and tracking red objects comprising a housing, a red LEDcoupled to the housing, a blue LED coupled to the housing, a powersource, and an actuator for activating the red LED and the blue LED. Thelight emitted by the red LED and the light emitted by the blue LED mixto create a magenta spot that is suitable for highlighting red material.

Yet another embodiment of the invention relates to a method ofhighlighting a red material comprising illuminating the red materialwith both red and blue light. The red and blue light mix to produce amagenta spot, which when illuminating a red colored material, makes thered material appear orange to the human eye.

BRIEF DESCRIPTION

FIG. 1 is a front elevation view of a tracking device.

FIG. 2 is a side elevation view of a tracking device.

FIG. 3 is a perspective view of a tracking device.

FIG. 4 is an elevation view of an LED array.

FIG. 5 is an elevation view of an LED array.

FIG. 6 is an elevation view of an LED array.

FIG. 7 is an elevation view of an LED array.

FIG. 8 is an elevation view of an LED array.

FIG. 9 is an elevation view of an LED array.

FIG. 10 is an elevation view of an LED array.

FIG. 11 is an elevation view of an LED array.

DETAILED DESCRIPTION

Color perception cannot be attributed directly and solely to wavelengthsof light. The eye focuses slightly differently on long wavelengths(reds) than on short wavelengths (blues). According to an exemplaryembodiment of the present invention, a tracking device may include amultiple color light source having a red LED light beam and a blue LEDlight beam that create an illusion causing the eye to see red objects inlow level lighting conditions as blaze orange. Simultaneouslyilluminating a red blood spot with the red LED beam and the blue LEDbeam of the system creates the desired highlighted orange blood effect.The highlighted blood appears orange and the surrounding backgroundgreen or brown flora appears blue/purple under the multi color LED beameven when the flora is wet.

In an exemplary embodiment, the blood tracking system is incorporatedinto a portable light source, such as a headlamp flashlight. Theheadlamp may have a removable, adjustable headband. The headlamp mayutilize a single AAA battery to provide power to the LEDs.Alternatively, multiple batteries may be used and the batteries may beof various sizes and types. The blood tracking system may be utilized inother portable light sources such as handheld flashlights and lanterns.

One headlamp into which the system may be incorporated is a TRACERheadlamp, sold by Gerber Legendary Blades, a Fiskars Brands Company. TheTRACER headlamp circuitry may be modified to incorporate a red and ablue LED. Trimming resistors, which may be adjusted to provide a desiredresistance, may be added to allow for varying the intensity of each LEDin order to generate a desired output.

In some embodiments, two distinct colors may be utilized. In anexemplary embodiment, one or more blue LEDs (i.e. LEDs having a peakwavelength centered in the range of about 410 nm to about 500 nm) may beused with one or more red LEDs (i.e. LEDs having a peak wavelength inthe range of about 600 nm to about 740 nm) to produce a spot thatappears to be magenta to a user. In some embodiments, an LED having anoutput centered at about 425 nm may be used with an a LED having anoutput centered at about 625 nm. In another exemplary embodiment, a redLED having a wavelength centered around 628 nm and a blue LED having awavelength centered around 470 nm may be used.

In some embodiments, the blood tracking system may include two LEDs (ared LED and a blue LED) that are simultaneously activated to provide thedesired blood tracking effect. In other embodiments, additional LEDs areused to increase the brightness of the light source, such as two redLEDs and two blue LEDs, or even more LEDs, such as 3-6 red LEDs and 3-6blue LEDs. The number of red LEDs may be greater or less than the numberof blue LEDs. Also, the intensity of the red LEDs may be greater of lessthan that of the blue LEDs.

In another embodiment, the red LED may be pulsed at a particularfrequency, which, when combined with the steady output of the blue LED,can enhance the visual signature of the blood or other red materialbeing tracked.

In some embodiments, the LEDs may be used individually, to provideeither red output or blue output separately. In other embodiments, otherLEDs may be added to the system, including other LEDs having differentcolors or wavelengths, such as infrared wavelengths. Circuitry may beutilized to provide different lighting options of the various LEDs andcombinations of LEDs.

The tracking device has several potential uses in addition to use in thehunting context described above. For example, the system may haveseveral potential military uses, such as by medics to determine thesource of blood on a body that is covered by dirt, mud, or othermaterial obscuring the wound providing the source of blood. Further,special forces personnel may utilize the invention to track enemycombatants that may have been wounded and are providing a blood trail.Also, the tracking device may be used by forensic analysts to findblood.

Referring to FIGS. 1-3, according to an exemplary embodiment, trackingdevice 10 includes a housing with a handle 12, and a head 14. Handle 12includes a grip portion 16, first power switch 18, a power supply 20,and a second power switch 22. Head 14 and handle 12 are shown coupled toeach other at an angle of about 90° and may be formed as a singleunitary body. Alternatively, head 14 and handle 12 may be coupled atother angles or in-line such that the head and handle extend alongeither the same longitudinal axis, or along longitudinal axes that aresubstantially parallel. In yet another embodiment, head 14 may berotatably coupled to handle 12 to allow a user to adjust the angleformed by head 14 and handle 12.

Handle 12 may include a grip portion 16 that includes grooves 24 for thefingers of a user to contact while using tracking device 10. Handle 12is shown as being generally straight along a longitudinal axis.Alternatively, other ergonomic configurations including a curved handlemay be used. Power supply 20 or handle 12 may include a removable cover26 which may cover a battery compartment. According to some embodiments,tracking device 10 may be adaptable to be used with alternating ordirect current from an external power source.

Head 14 may include a primary light source 30 and a secondary lightsource 32. Primary light source 30 may include a lamp 34, a reflector36, cap 38, and lens 40. Lamp 34 may be a xenon bulb. Alternatively,lamp 34 may be another type of incandescent bulb, or one or more whiteLEDs. Reflector 36 may be generally parabolic in shape to direct lightemitted from lamp 34 into a beam. Reflector 36 may be faceted or smooth.Primary light source 30 may include a cap 38 for securing the primarylight source 30 to head 14. Cap 38 may be threadably or otherwisecoupled to head 14. Lens 40 may be disposed within cap 38 to provide awater resistant seal for primary light source 30. According to someembodiments, reflector 36 may be coupled to cap 38 such that rotation ofcap 38 moves reflector 36 relative to lamp 34 whereby the width of thelight beam produced by primary light source 30 may be adjusted byrotating cap 38. Second power switch 22 may be used to turn primarylight source 30 on and off.

Secondary light source 32 may include an LED array 42, shown as eightLEDs of similar size in FIG. 1. A greater or lesser number of LEDs inother configurations may also be used. LED array 42 may be controlled byfirst power switch 18. In some embodiments, first power switch 18 maysimultaneously deactivate primary light source 30 and activate LED array42.

In some embodiments, tracking device 10 may optionally include a powerindicator 44, shown as three LEDs, that may be used to indicate thestrength of batteries used to power tracking device 10. Alternatively, agreater or lesser number of LEDs in other configurations may also beused to indicate battery strength. Also, power indicator 44 may beplaced in a variety of positions on tracking device 10. Secondary lightsource 32 may be covered by lens 46 to protect LED array 42 and powerindicator 44.

According to some embodiments, removable cover 26 may include anoptional coupling point 28 which may be used to attach a lanyard totracking device 10. Alternatively, a coupling point for a lanyard may beprovided elsewhere on tracking device 10.

Referring to FIG. 4, LED array 42 may include a total of eight LEDs 48and 50. According to some embodiments, LEDs 48 may be blue while LEDs 50are red. Alternatively, LEDs 48 may be red while LEDs 50 are blue.

Referring to FIG. 5, an LED array for use in a tracking device mayinclude a total of six LEDs. According to some embodiments, LEDs 52 maybe blue while LEDs 54 are red. Alternatively, LEDs 52 may be red whileLEDs 54 are blue.

Referring to FIG. 6, an LED array for use in a tracking device mayinclude LED dies (i.e. components made of a semiconductor material usedto generate light in an LED). According to some embodiments one or morered LED dies 56 may be used with one or more blue LED dies 58. The LEDdies may be focused and tuned to produce a homogenous magenta spot.

Referring to FIG. 7, an LED array for use in a tracking device mayalternatively include one or more red LED dies 60 may be used with oneor more blue LED dies 62 and one or more green LED dies 64 where thegreen output is kept to a low level relative to the red and blue outputsto avoid diminishing the highlighting effect of the tracking device.

Referring to FIG. 8, an LED array for use in a tracking device mayinclude a bicolor LED 66. According to some embodiments one or more redemitter outputs 68 may be used with one or more blue emitter outputs 70.The LED emitter outputs may be focused and tuned to produce a homogenousmagenta spot.

Referring to FIG. 9, an LED array for use in a tracking device mayinclude a tricolor LED 72. According to some embodiments, the tricolorLED 72 may include one or more red emitter outputs 74, one or more blueemitter outputs 76, and one or more green emitter outputs 78. The LEDemitter outputs may be focused and tuned to produce a homogenous magentaspot.

Referring to FIG. 10, an LED array for use in a tracking device mayinclude a magenta LED 80. The magenta LED 80 may include an emitter 82designed to emit a magenta output (i.e. a combination of blue and redwavelengths).

Referring to FIG. 11, a white LED 84 may be used with a filter 86.Filter 86 may absorb green light while transmitting and balancing blueand red light to create a magenta beam. Alternatively, a plurality offilters may be used create a magenta beam. In some embodiments, aplurality of light sources, such as white LEDs may be used with filtersto create a magenta beam. For example, one light source including one ormore white LEDs and a blue filter may be used with a second light sourceincluding one or more white LEDs and a red filter.

While the detailed drawings and specific examples given describe variousexemplary embodiments of the blood tracking system, they serve thepurpose of illustration only. It is to be understood that the inventionis not limited in its application to the details of construction and thearrangements of components set forth in the preceding description orillustrated in the drawings. For example, other arrangements of LEDs maybe used to create the desired blood tracking effect, or the flashlightmay be one of a variety of configurations known in the art. Furthermore,other substitutions, modifications, changes, and omissions may be madein the design, operating conditions, and arrangements of the exemplaryembodiments without departing from the scope of the invention asexpressed in the appended claims.

1. A blood tracking system, comprising: a light source, comprising: afirst LED configured to emit light of a first color; and a second LEDconfigured to emit light of a second color; wherein the light of thefirst color and the light of the second color are mixed to produce lightof a third color when the first LED and the second LED are activated;and wherein the light of the third color highlights blood.
 2. The bloodtracking system of claim 1, wherein the first color is red, the secondcolor is blue, and the third color is a combination of red and blue. 3.The blood tracking system of claim 2, wherein the third color ismagenta.
 4. The blood tracking system of claim 1, wherein the lightsource is coupled to a handheld flashlight.
 5. The blood tracking systemof claim 1, wherein the light source is coupled to a headlampflashlight.
 6. The blood tracking system of claim 1, further comprisinga second light source comprising an emitter of white light.
 7. The bloodtracking system of claim 6, wherein the second light source furthercomprises a reflector and a lens.
 8. A flashlight for detecting andtracking blood, comprising: a housing; a first LED configured to emitlight of a first color, the first LED coupled to the housing; a secondLED configured to emit light of a second color, the second LED coupledto the housing; a power source, and an actuator for activating the firstLED and the second LED; wherein the light emitted by the first LED andthe light emitted by the second LED mix to create a light beam thathighlights blood.
 9. The flashlight of claim 8, wherein the housing isconfigured for use as a headlamp flashlight.
 10. The flashlight of claim8, wherein the housing is configured for use as a handheld flashlight.11. The flashlight of claim 8, wherein the first LED emits light at apeak wavelength in the range of about 600 nm to about 740 nm.
 12. Theflashlight of claim 8, wherein the second LED emits light at a peakwavelength in the range of about 410 nm to about 500 nm.
 13. Theflashlight of claim 8, wherein the first LED emits light at a peakwavelength of about 628 nm, and the second LED emits light at a peakwavelength of about 470 nm.
 14. The flashlight of claim 8, furthercomprising an a light source emitting white light.
 15. The flashlight ofclaim 14, wherein the light source further comprises a reflector and alens.
 16. A method of highlighting blood using the blood tracking systemof claim 1, comprising: activating the first LED to emit the light ofthe first color; activating the second LED to emit the light of thesecond color while the first LED is still activated, wherein the lightof the first color and the light of the second color are thereby mixedto produce a light of a third color; and illuminating blood with thelight of the third color; wherein the light of the third colorhighlights the blood.
 17. The method of claim 16, wherein the light ofthe first color and light of a second color are provided by a flashlightcomprising a red LED and a blue LED.